Managing men: women's dilemmas about overt and covert use of barrier methods for HIV prevention.

Women in sub-Saharan Africa are at high risk of HIV infection and may struggle to negotiate condom use. This has led to a focus on the development of female-controlled barrier methods such as the female condom, microbicides and the diaphragm. One of the advantages of such products is their contribution to female empowerment through attributes that make covert use possible. We used focus groups to discuss covert use of barrier methods with a sample of South African women aged 18-50 years from Eastern Johannesburg. Women's attitudes towards covert use of HIV prevention methods were influenced by the overarching themes of male dislike of HIV and pregnancy prevention methods, the perceived untrustworthiness of men and social interpretations of female faithfulness. Women's discussions ranged widely from overt to covert use of barrier methods for HIV prevention and were influenced by partner characteristics and previous experience with contraception and HIV prevention. The discussions indicate that challenging gender norms for HIV prevention can be achieved in quite subtle ways, in a manner that suits individual women's relationships and previous experiences with negotiation of either HIV or pregnancy prevention.

Integrating tuberculosis and HIV services for people living with HIV: costs of the Zambian ProTEST Initiative.

BACKGROUND: In the face of the dual TB/HIV epidemic, the ProTEST Initiative was one of the first to demonstrate the feasibility of providing collaborative TB/HIV care for people living with HIV (PLWH) in poor settings. The ProTEST Initiative facilitated collaboration between service providers. Voluntary counselling and testing (VCT) acted as the entry point for services including TB screening and preventive therapy, clinical treatment for HIV-related disease, and home-based care (HBC), and a hospice. This paper estimates the costs of the ProTEST Initiative in two sites in urban Zambia, prior to the introduction of anti-retroviral therapy. METHODS: Annual financial and economic providers costs and output measures were collected in 2000-2001. Estimates are made of total costs for each component and average costs per: person reached by ProTEST; VCT pre-test counselled, tested and completed; isoniazid preventive therapy started and completed; clinic visit; HBC patient; and hospice admission and bednight. RESULTS: Annual core ProTEST costs were (in 2007 US dollars) $84,213 in Chawama and $31,053 in Matero. The cost of coordination was 4%-5% of total site costs ($1-$6 per person reached). The largest cost component in Chawama was voluntary counselling and testing (56%) and the clinic in Matero (50%), where VCT clients had higher HIV-prevalences and more advanced HIV. Average costs were lower for all components in the larger site. The cost per HBC patient was $149, and per hospice bednight was $24. CONCLUSION: This study shows that coordinating an integrated and comprehensive package of services for PLWH is relatively inexpensive. The lessons learnt in this study are still applicable today in the era of ART, as these services must still be provided as part of the continuum of care for people living with HIV.

Evaluation of a workplace HIV treatment programme in South Africa.

OBJECTIVE: To review the experience of implementing a workplace HIV care programme in South Africa and describe treatment outcomes in sequential cohorts of individuals starting antiretroviral therapy (ART). DESIGN: A review of an industrial HIV care and treatment programme. Between October 2002 and December 2005, 2262 patients enrolled in the HIV care programme. RESULTS: CD4 cell counts increased by a median of 90, 113 and 164 cells/microl by 6, 12 and 24 months on treatment, respectively. The viral load was suppressed below 400 copies/ml in 75, 72 and 72% of patients at 6, 12 and 24 months, respectively, at an average cost of US$1654, 3567 and 7883 per patient virally suppressed, respectively. Treatment outcomes in sequential cohorts of patients were consistent over time. A total of 93.6% of patients at 14,752 clinic visits reported missing no tablets over the previous 3 days. Almost half the patients (46.8%) experienced one or more adverse events, although most were mild (78.7%). By the end of December 2005, 30% of patients were no longer on ART, mostly because of defaulted or stopped treatment (12.8%), termination of employment (8.2%), or death (4.9%). CONCLUSION: This large workplace programme achieved virological results among individuals retained in the programme comparable to those reported for developed countries; more work is needed to improve retention. Monitoring treatment outcomes in sequential cohorts is a useful way of monitoring programme performance. As the programme has matured, the costs of programme implementation have reduced. Counselling is a central component of an ART programme. Challenges in implementing a workplace ART programme are similar to the challenges of public-sector programmes.

A cost function for HIV prevention services: is there a 'u' - shape?

BACKGROUND: Global resource needs estimation is a critical part of addressing the HIV/AIDS epidemic. To generate these estimates knowledge of costs and cost structures is required. The evidence base for costs of HIV prevention programmes is limited. Even less is known about the existence of economies scale and whether, as economic theory suggests, average costs form a 'u'-shaped curve as scale increases. Using an econometric analysis, this paper addresses this question by estimating marginal costs and economies of scale for HIV prevention programmes for vulnerable groups in Southern India with different levels of coverage. METHODS: Two hybrid translog-cost functions were estimated. First, expenditure data from 78 state-funded HIV prevention projects in Andhra Pradesh were used to explore the impact of scale, institutional history and price on costs; second, economic cost data from 16 commercial sex worker projects across Tamil Nadu and Andhra Pradesh were analysed to additionally assess the impact of the value of inputs not reported in expenditure data and location. Coefficient estimates were used to calculate marginal costs and economies of scale. RESULTS: The econometric model yielded a good fit (R2 = 0.46, p < 0.001 and R2 = 0.79, p < 0.001, for the expenditure and economic cost datasets, respectively). The economies of scale index was greater than 1 for both datasets and fell as coverage increased. Analysis of the expenditure data found economies of scale were not exhausted, with a 0.002% change in total cost for each extra person reached and an 11% difference in total cost between target group categories. Estimation using the economic cost data suggests a point of minimum efficient scale at around 1750-2000 people reached, a 0.03% change in total cost for each extra person reached, and 28% lower costs in Tamil Nadu than Andhra Pradesh. CONCLUSION: Econometric analysis of these standardized datasets provides insights into how costs change with coverage, the impact of project location and nature of the project target group. The results demonstrate the importance of understanding the nature of the cost function when designing, budgeting and estimating resource requirements for scaling up coverage of HIV prevention projects.

Financing and cost-effectiveness analysis of public-private partnerships: provision of tuberculosis treatment in South Africa.

BACKGROUND: Public-private partnerships (PPP) could be effective in scaling up services. We estimated cost and cost-effectiveness of different PPP arrangements in the provision of tuberculosis (TB) treatment, and the financing required for the different models from the perspective of the provincial TB programme, provider, and the patient. METHODS: Two different models of TB provider partnerships are evaluated, relative to sole public provision: public-private workplace (PWP) and public-private non-government (PNP). Cost and effectiveness data were collected at six sites providing directly observed treatment (DOT). Effectiveness for a 12-month cohort of new sputum positive patients was measured using cure and treatment success rates. Provider and patient costs were estimated, and analysed according to sources of financing. Cost-effectiveness is estimated from the perspective of the provider, patient and society in terms of the cost per TB case cured and cost per case successfully treated. RESULTS: Cost per case cured was significantly lower in PNP (US $354-446), and comparable between PWP (US $788-979) and public sites (US $700-1000). PPP models could significantly reduce costs to the patient by 64-100%. Relative to pure public sector provision and financing, expansion of PPPs could reduce government financing required per TB patient treated from $609-690 to $130-139 in PNP and $36-46 in PWP. CONCLUSION: There is a strong economic case for expanding PPP in TB treatment and potentially for other types of health services. Where PPPs are tailored to target groups and supported by the public sector, scaling up of effective services could occur at much lower cost than solely relying on public sector models.

The cost-effectiveness of HIV preventive measures among injecting drug users in Svetlogorsk, Belarus.

AIM: To undertake a cost-effectiveness analysis of a harm reduction and HIV prevention project for injecting drug users (IDUs) in Eastern Europe. Economic evaluation methods were adapted to consider the effect of an 8-month financing gap that negatively impacted on project implementation. DESIGN: Financial and economic costs of implementing the intervention were analysed retrospectively. The data were also modelled to estimate the costs of a fully functioning project. Estimates of the intervention impact on sexual and drug injecting behaviour were obtained from existing pre- and post-intervention behavioural surveys of IDUs. A dynamic mathematical model was used to translate these changes into estimates of HIV infections averted among IDUs and their sexual partners. Projections of the potential effect of the shortfall in funding on the impact and cost-effectiveness of the intervention were made. SETTING: Svetlogorsk, Belarus, where in 1997 the IDU HIV prevalence was 74%. FINDINGS: The intervention averted 176 HIV infections (95% CI 60-270) with a cost-effectiveness of 359 dollars per HIV infection averted (95% CI 234-1054 dollars). Without the 2311 dollars reduction (7%) in financing, the estimated cost-effectiveness ratio of the project would have been 11% lower. The costing methods used to measure donated mass media can substantially influence cost and cost-effectiveness estimates. CONCLUSIONS: Harm reduction activities among IDUs can be cost-effective, even when IDU HIV prevalence and incidence is high. Relatively small shortfalls in funding reduce impact and cost-effectiveness. Increased and consistent allocation of resources to harm reduction projects could significantly reduce the pace of the HIV epidemic in Eastern Europe.

Malaria incidence in rural Benin: does economics matter in endemic area?

Malaria represents a major health problem with over 1 million annual deaths in Africa alone. There are a limited number of policies tackling the health problems of people at greater risk, namely the poor and rural communities. This is partly due to the lack of evidence available on the range of factors affecting their health status. Despite endemic malarial situations, there is still little understanding of the relative importance of economic factors that contribute to people acquiring malaria. This paper examines the socio-economic and economic factors that affect the incidence of malaria in rural community households in Benin, where malaria is endemic. A sample of 1585 households was determined to collect information on socio-economic characteristics and the presence of malaria symptoms. Probit estimation techniques were used to assess the impact of socio-demographic and socio-economic factors on the incidence of malaria, comparing households with and without malaria patients. Predisposing characteristics of the household head such as age, knowledge of malaria, education and the size of the household significantly affect the incidence of malaria as anticipated by economic theory. Enabling factors reflecting higher economic status, measured by monthly expenditure and a socio-economic index, have a statistically significant and positive impact on the incidence of malaria. This could reflect that better-off have improved case reporting and are likely to seek treatment. Variations in socio-economic and economic characteristics are significant in explaining the incidence of malaria, even in an endemic malarial setting.

The motivations for participation in public-private partnerships for the provision of tuberculosis treatment in South Africa.

There is increasing interest in public-private partnerships (PPPs) generally, and more specifically for the provision of tuberculosis (TB) treatment, yet little is known about the motivations for such partnerships and the nature of the incentives that are required to achieve a desirable outcome of the partnerships. Using the new institutional economics approach, this study examines the motivations for participation in existing and potential models of PPPs for the provision of TB treatment in South Africa. Fourteen semi-structured interviews were conducted with private providers and government officials. Both current and potential private partners were interviewed. The study found that private providers in existing and potential partnerships appear to have both financial and non-financial motivations for participation in partnership for the provision of TB. For a partnership to be successful, in addition to sufficient motivation, the level of competition between private providers, regulatory framework, and social and political awareness becomes increasingly important.

The cost-effectiveness of consistent and early intervention of harm reduction for injecting drug users in Bangladesh.

AIMS: To assess the cost-effectiveness of the CARE-SHAKTI harm reduction intervention for injecting drug users (IDUs) over a 3-year period, the impact on the cost-effectiveness of stopping after 3 years and how the cost-effectiveness might vary with baseline human immunodeficiency virus (HIV) prevalence. DESIGN: Economic cost data were collected from the study site and combined with impact estimates derived from a dynamic mathematical model. SETTING: Dhaka, Bangladesh, where the HIV prevalence has remained low despite high-risk sexual and injecting behaviours, and growing HIV epidemics in neighbouring countries. FINDINGS: The cost per HIV infection prevented over the first 3 years was USD 110.4 (33.1-182.3). The incremental cost-effectiveness of continuing the intervention for a further year, relative to stopping at the end of year 3, is USD 97 if behaviour returns to pre-intervention patterns. When baseline IDU HIV prevalence is increased to 40%, the number of HIV infections averted is halved for the 3-year period and the cost per HIV infection prevented doubles to USD 228. CONCLUSIONS: The analysis confirms that harm reduction activities are cost-effective. Early intervention is more cost-effective than delaying activities, although this should not preclude later intervention. Starting harm reduction activities when IDU HIV prevalence reaches as high as 40% is still cost-effective. Continuing harm reduction activities once a project has matured is vital to sustaining its impact and cost-effectiveness.

The economics of scaling up: cost estimation for HIV/AIDS interventions.

BACKGROUND: The scaling up of HIV/AIDS programming has been one of the most extensive undertakings in international public health. Yet decision-makers are encountering significant uncertainties about financing and the need to understand programming costs at different scales of delivery. OBJECTIVES: To review the economic methodologies for examining costs and variation by scale. To summarize and synthesize the current evidence related to the provision of HIV/AIDS interventions and scaling up. METHODS: We used a review of economic methodologies to generate a conceptual framework for classifying existing data, looking at both short-run and long-run perspectives. A review of the literature was performed using PubMed and available grey literature. Factors facilitating comparison and generalizability are highlighted. RESULTS: There is growing evidence of scale variation among the costs of HIV/AIDS interventions. Scale variation has been found to explain 26-70% of cost variation across locations for similar interventions. Average costs may become larger or smaller as the volume of services expands, depending on the level of coverage and type of intervention. Key constraints to scaling up include infrastructure investments and cost results need to be interpreted in this light. CONCLUSIONS: Evidence to date suggests that cost efficiencies associated with scale may reflect different ways of delivering services at higher volumes, including lower quality outputs. There is still, however, an extremely limited economic evidence base and mechanisms to integrate economic analyses into routine programme monitoring are recommended.

Male circumcision for HIV prevention in sub-Saharan Africa: who, what and when?

BACKGROUND AND OBJECTIVE: Male circumcision (circumcision) reduces HIV incidence in men by 50-60%. The United Nations Joint Programme on HIV/AIDS (UNAIDS) recommends the provision of safe circumcision services in countries with high HIV and low circumcision prevalence, prioritizing 12-30 years old HIV-uninfected men. We explore how the population-level impact of circumcision varies by target age group, coverage, time-to-scale-up, level of risk compensation and circumcision of HIV infected men. DESIGN AND METHODS: An individual-based model was fitted to the characteristics of a typical high-HIV-prevalence population in sub-Saharan Africa and three scenarios of individual-level impact corresponding to the central and the 95% confidence level estimates from the Kenyan circumcision trial. The simulated intervention increased the prevalence of circumcision from 25 to 75% over 5 years in targeted age groups. The impact and cost-effectiveness of the intervention were calculated over 2-50 years. Future costs and effects were discounted and compared with the present value of lifetime HIV treatment costs (US$ 4043). RESULTS: Initially, targeting men older than the United Nations Joint Programme on HIV/AIDS recommended age group may be the most cost-effective strategy, but targeting any adult age group will be cost-saving. Substantial risk compensation could negate impact, particularly if already circumcised men compensate. If circumcision prevalence in HIV uninfected men increases less because HIV-infected men are also circumcised, this will reduce impact in men but would have little effect on population-level impact in women. CONCLUSION: Circumcision is a cost-saving intervention in a wide range of scenarios of HIV and initial circumcision prevalence but the United Nations Joint Programme on HIV/AIDS/WHO recommended target age group should be widened to include older HIV-uninfected men and counselling should be targeted at both newly and already circumcised men to minimize risk compensation. To maximize infections-averted, circumcision must be scaled up rapidly while maintaining quality.

Treating curable sexually transmitted infections to prevent HIV in Africa: still an effective control strategy?

BACKGROUND: Evidence regarding the effectiveness of sexually transmitted infection (STI) treatment for HIV prevention in Africa is equivocal, leading some policy makers to question whether it should continue to be promoted for HIV control. We explore whether treating curable STIs remains a cost-effective HIV control strategy in Africa. METHODS: The model STDSIM was fitted to the characteristics of 4 populations in East and West Africa. Over the simulated HIV epidemics, the population-attributable fractions (PAFs) of incident HIV attributable to STIs, the impact of syndromic STI management on HIV incidence, and the cost per HIV infection averted were evaluated and compared with an estimate of lifetime HIV treatment costs (US $3500). RESULTS: Throughout the HIV epidemics in all cities, the total PAF for. all STIs remained high, with > or = 50% of HIV transmission attributed to STIs. The PAF for herpes simplex virus type 2 increased during the epidemics, whereas the PAF for curable STIs and the relative impact of syndromic management decreased. The models showed that the absolute impact of syndromic management remains high in generalized epidemics, and it remained cost-saving in 3 of the 4 populations in which the cost per HIV infection averted ranged between US $321 and $1665. CONCLUSION: Curable STI interventions may remain cost-saving in populations with generalized HIV epidemics, particularly in populations with high-risk behaviors or low male circumcision rates.

Sharing the burden of TB/HIV? Costs and financing of public-private partnerships for tuberculosis treatment in South Africa.

OBJECTIVE: To explore the economic costs and sources of financing for different public-private partnership (PPP) arrangements to tuberculosis (TB) provision involving both workplace and non-profit private providers in South Africa. The financing required for the different models from the perspective of the provincial TB programme, provider, and the patient are considered. METHOD: Two models of TB provider partnerships were evaluated, relative to sole public provision: public-private workplace (PWP) and public-private non-government (PNP). The cost analysis was undertaken from a societal perspective. Costs were collected retrospectively to consider both the financial and economic costs. Patient costs were estimated using a retrospective structured patient interview. RESULTS: Expansion of PPPs could potentially lead to reduced government sector financing requirements for new patients: government financing would require $609-690 per new patient treated in the purely public model, in contrast to PNP sites which would only need to $130-139 per patient and $36-46 with the PWP model. Moreover, there are no patient costs associated with the treatment in the employer-based facilities and the cost to the patient supervised in the community is, on average, three times lower than in public sector facilities. CONCLUSIONS: The results suggest that there is a strong economic case for expanding PPP involvement in TB treatment in the process of scaling up. The cost to the government per new patient treated could be reduced by enhanced partnership between the private and public sectors.

Constructing socio-economic status indices: how to use principal components analysis.

Theoretically, measures of household wealth can be reflected by income, consumption or expenditure information. However, the collection of accurate income and consumption data requires extensive resources for household surveys. Given the increasingly routine application of principal components analysis (PCA) using asset data in creating socio-economic status (SES) indices, we review how PCA-based indices are constructed, how they can be used, and their validity and limitations. Specifically, issues related to choice of variables, data preparation and problems such as data clustering are addressed. Interpretation of results and methods of classifying households into SES groups are also discussed. PCA has been validated as a method to describe SES differentiation within a population. Issues related to the underlying data will affect PCA and this should be considered when generating and interpreting results.

Costs of measures to control tuberculosis/HIV in public primary care facilities in Cape Town, South Africa.

OBJECTIVE: To measure the costs and estimate the cost-effectiveness of the ProTEST package of tuberculosis/human immunodeficiency virus (TB/HIV) interventions in primary health care facilities in Cape Town, South Africa. METHODS: We collected annual cost data retrospectively using ingredients-based costing in three primary care facilities and estimated the cost per HIV infection averted and the cost per TB case prevented. FINDINGS: The range of costs per person for the ProTEST interventions in the three facilities were: US$ 7-11 for voluntary counselling and testing (VCT), US$ 81-166 for detecting a TB case, US$ 92-183 for completing isoniazid preventive therapy (IPT) and US$ 20-44 for completing six months of cotrimoxazole preventive therapy. The estimated cost per HIV infection averted by VCT was US$ 67-112. The cost per TB case prevented by VCT (through preventing HIV) was US$ 129-215, by intensified case finding was US$ 323-664 and by IPT was US$ 486-962. Sensitivity analysis showed that the use of chest X-rays for IPT screening decreases the cost-effectiveness of IPT in preventing TB cases by 36%. IPT screening with or without tuberculin purified protein derivative screening was almost equally cost-effective. CONCLUSION: We conclude that the ProTEST package is cost saving. Despite moderate adherence, linking prevention and care interventions for TB and HIV resulted in the estimated costs of preventing TB being less than previous estimates of costs of treating it. VCT was less expensive than previously reported in Africa.

The costs of treating curable sexually transmitted infections in low- and middle-income countries: a systematic review.

BACKGROUND: Calls for increased investment in sexually transmitted infection (STI) treatment across the developing world have been made to address the high disease burden and the association with HIV transmission. GOALS: The goals of this study were to systematically review evidence on the cost of treating curable STIs and to explore its key determinants. STUDY: A search of published literature was conducted in PubMed and supplemented by reviews of gray literature. Studies were analyzed by broad focus. Regression analysis explored how intervention characteristics affect unit costs, accounting for differences in costing methods. RESULTS: Fifty-three primary studies were identified, of which 62% used empirical data, 35% presented economic costs, and 22% presented full costs. The median STI treatment cost was US dollars 17.80. Clinics serving symptomatic patients were consistently cheaper than outreach services, services using syndromic management protocols had lower costs, and unit costs decreased with scale. CONCLUSIONS: The compiled cost data provide an evidence base that can be used to help inform resource planning.

Are targeted HIV prevention activities cost-effective in high prevalence settings? Results from a sexually transmitted infection treatment project for sex workers in Johannesburg, South Africa.

OBJECTIVE: The objective of this study was to estimate the cost-effectiveness of syndromic management, with and without periodic presumptive treatment (PPT), in averting sexually transmitted infections (STIs) and HIV in female sex workers (FSWs) participating in a hotel-based intervention in Johannesburg. STUDY DESIGN: Financial and economic providers' costs were estimated. A mathematical model, fitted to epidemiologic data, projected the HIV and STIs averted by the intervention. Cost per HIV infection and DALY averted were estimated for different general population HIV prevalences. RESULTS: Projections suggest 53 HIV infections were averted (July 2000-June 2001) and a 3.1% decrease in the FSW HIV incidence. Cost-effectiveness was US dollars 78 per DALY averted. Incremental cost of PPT was US dollars 31 per disability-adjusted life year (DALY) averted. Initiating the intervention at 15% general HIV prevalence would have improved cost-effectiveness by 35%. Expanding PPT coverage to mass-treat all FSWs (instead of <17%) and their clients could increase impact 14-fold. CONCLUSION: The results highlight targeted interventions can be cost-effective at all stages of HIV epidemics and suggests PPT could improve the cost-effectiveness of targeted STI interventions.

The cost-effectiveness of expanding harm reduction activities for injecting drug users in Odessa, Ukraine.

OBJECTIVES: The objectives of this study were to estimate the cost-effectiveness of a harm reduction intervention among injecting drug users (IDUs) in Odessa, Ukraine; and to explore how the cost-effectiveness changes if the intervention were scaled up to 60% as recommended by WHO/UNAIDS. STUDY DESIGN: Economic providers' costs were estimated. A dynamic mathematical model, fitted to epidemiologic data, projected the intervention's impact. The cost per HIV infection averted for different intervention coverages was estimated. RESULTS: From September 1999 to August 2000, at the current coverage of between 20% to 38% and an injection drug user (IDU) HIV prevalence of 54%, projections suggest 792 HIV infections were averted, a 22% decrease in IDU HIV incidence, but a 1% increase in IDU HIV prevalence. Cost per HIV infection averted was $97. Scaling up the intervention to reach 60% of IDUs remains cost-effective and reduces HIV prevalence by 4% over 5 years. CONCLUSION: At the current coverage, the harm reduction intervention in Odessa is cost-effective but is unlikely to reduce IDU HIV prevalence in the short-term. To reduce HIV prevalence, more resources are needed to increase coverage.

From trial intervention to scale-up: costs of an adolescent sexual health program in Mwanza, Tanzania.

OBJECTIVE: To estimate annual costs of a multifaceted adolescent sexual health intervention in Mwanza, Tanzania, by input (capital and recurrent), component (in-school, community activities, youth-friendly health services, condom distribution), and phase (development, startup, trial implementation, scale-up). STUDY DESIGN: Financial and economic providers' costs and intervention outputs were collected to estimate annual total and unit costs (1999-2001). The incremental financial budget projects funding requirements for scale-up within an integrated model. RESULTS: The 3-year economic costs of trial implementation were US dollars 879,032, of which approximately 70% were for the school-based component. Costs of initial development and startup were relatively substantial ( approximately 21% of total costs); however, annual costs per school child dropped from US dollars 16 in 1999 to US dollars 10 in 2001. The incremental scale-up cost is approximately 1/5 of ward trial implementation running costs. CONCLUSIONS: Annual costs can reduce by almost 40% as project implementation matures. When scaled up, only an additional US dollars 1.54 is needed per pupil per year to continue the intervention.

The role of community acceptance over time for costs of HIV and STI prevention interventions: analysis of the Masaka Intervention Trial, Uganda, 1996-1999.

OBJECTIVE: The objective of this study is to estimate the annual costs of information, education, and communication (IEC), both community- and school-based; strengthened public and private sexually transmitted infections treatment; condom social marketing (CSM); and voluntary counseling and testing (VCT) implemented in Masaka, Uganda, over 4 years, and to explore how unit costs change with varying population use/uptake. STUDY: Total economic provider's costs and intervention outputs were collected annually to estimate annual unit costs between 1996 and 1999. RESULTS: In early intervention years, uptake of all activities grew dramatically and continued to grow for public STI treatment, CSM, and VCT. Attendance at IEC performances started to drop in year 4. Unit costs dropped rapidly with increasing uptake of and participation in interventions. CONCLUSIONS: When implementing long-term community-based interventions, it is important to take into account that it takes time for communities to scale up their participation, since this can lead to large variations in unit costs.